During a well drilling operation, cement casing is typically inserted into the borehole to provide structural support for the borehole in unstable geological formations in addition to sealing the borehole. The casing is typically cemented in place by circulating a cement slurry through the inside of the casing and out into the annulus through a casing shoe at the bottom of the casing string.
In an offshore drilling operation, the cementing operation may be accomplished by an offshore cementing skid. One or more electric motors on the skid provide the pressure used to inject the cement into the wellbore. It is desirable to control the operation of these motors in order to control the flow of cement into the wellbore.